Hitachi SJ700-2 instruction manual Example 4 Restarting with active matching frequency

Chapter 4 Explanation of Functions

(Example 1)

RS

Alarm

(Example 2)

RS

Alarm

(Example 3)If you select "01" (starting with matching frequency) as the restart mode after reset (C103), you can also make the inverter start the motor with matching frequency after the power reset. When "00" (starting with 0 Hz) is selected as the restart mode after reset (C103), the setting of the retry wait time before motor restart (b003) is ignored. Note that, even when restarting with matching frequency has been selected, the inverter may start the motor with 0 Hz if:

1)the output frequency is no more than half the base frequency or

2)the voltage induced on the motor is attenuated quickly.

3)the restart frequency threshold (b007) is set and the detected frequency is lower than that.

FW

Starting with matching

Free running frequency

Motor speed

Note: The reset operation clears the inverter's internal counters that are used for protective functions. Therefore, if you intend to use an intelligent input terminal to shut off the inverter output, use the free-run stop (FRS) terminal.

(Example 4) Restarting with active matching frequency

FW

RS

b028

Output current

Deceleration according to the setting of "b029"

Inverter output frequency

Occurrence of trip	Frequency selected as the
	setting of "b030"

Motor speed

b003

After the retry wait time (b003), the inverter restarts the motor with the frequency set as "b030". The inverter subsequently decelerates the motor according to the setting of "b029" while maintaining the output current at the level specified for "b029". When the output voltage matches the frequency, the inverter re-accelerates the motor up to the frequency that was set when the inverter shut off the output to the motor before the restart.

If the inverter trips because of overcurrent when it restarts the motor with input frequency, reduce the setting of "b028".

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